David d



(No Model.)

D. D. LA BAW.

CLAMP FOR DUMB WAITERSm No. 310,687. Patented Jan. 13,1885.

NITE "rates FFICE.

I DAVID D. LA BAWV, OE JERSEY CITY, NEl/V JERSEY.

CLAMP FOR DUMB WAITERS.

SPECIFICATION forming part of Letters Patent No, 310,687, dated January 13, 1885.

Application filed June 16, 1884.

To aZZ whom it may concern.-

Be it known that I, DAVID D. Ln Bilw, of Jersey City, in the county of Hudson and State of New Jersey, have invented an Improvement in Clamps for Dumb-WVaiters, of which the following is a specification.

Dumb-waiters have been made with a counter-weight, and also with a barrel upon which the rope to the waiter is wound or unwound, and an endless rope has passed around the hoist-wheel upon the axleof the barrel, and a clamp has been applied by hand to hold the hoist-rope.

My present invention relates to the combination, with the hoist-rope, of a self-acting clamp by which the waiter is held at any place to which it may have been moved, and a foot-lever that is used to relieve the clamp, so that the hands are at liberty to take off or place on the waiter any article, or to operate the hoist-rope, and when the foot-lever is operated the clamp is released and the waiter free to descend by the weight, or any desired amount of frictional detention is applied to the hoist-rope so as to regulate the speed with which the waiter descends.

In the drawings, Figure l is an elevation illustrating the manner in which the clamp is applied to the waiter. Fig. 2 is a side view of the clamp and lever, and Fig. 3 is a sectional plan of the clamp in larger size.

The waiter A is provided with shelves and vertical guide-slides. The rope B from the same goes over the drum 0, and is usually passed partially around a guide-pulley, D, and over the pulley E to the weight F, in a box, G.

Upon the shaft of the drum 0 there is a hoist-wheel, H, the edge of which is grooved deeply for the hoist-rope I, which is endless, and passes vertically from such hoist-wheel through the various floors, and sometimes be low guide-pulleys at the bottom.

The clamp for the rope is made of the fixed part K and the moving part L, with the faces grooved and preferably lined with indiarubher. The two parts of the clamp are connected by the parallel links a, pivoted at the ends to the respective clamps so that the clamp opens when the moving part is drawn (No model.)

down, and the links are nearly horizontal, and the clamps close when the moving part is drawn up by the cord at and weight 19, and the links swing into an inclined position. The cord m, passing over the pulley 0 and being acted upon by the weight 19, tends at all times to lift the moving portion L of the clamp and make the sameautomatic in stopping the waiter and preventing it running down by any weight placed upon it.

I provide a rod, 15, connected with the moving part L of the clamp, and to this a treadle or lever, u, is attached, at or near the floor, so that when the foot is placed upon the treadle the clamp is opened and the rope liberated, and the waiter will run down until its movement is arrested. It will be apparent that this rod t may be extended vertically through the floors of the building and a lever or treadles connected at each floor, so that the clamp may be liberated with facility by operating either treadle, and as soon as the treadle is released the clamp holds the waiter-rope and stops the waiter.

I claim as my invention- 1. The combination, with the hoist-rope and dumb-waiter, of a clamp acting upon the hoist-rope, and a cord and weight to close the same, substantially as set forth.

2. The combination, with the hoist-rope and dumb-waiter, of a clamp having grooved faces, parallel links for opening or closing the same, a cord and weight to move the clamp to close the same, and a rod or connection and a lever for opening the same, substantially as set forth.

3. The combination, with the hoist-rope and dumb-waiter, of a clamp having grooved faces lined with india-rubber, parallel links connecting the moving portion of the clamp to the fixed portion, a rope and weight to close the clamp, and a lever and rod to open the same, as specified.

Signed by me this 9th day of June, A. D. 1884.

DAVID D. LA BAW.

WVitnesses:

GEO. T. PINOKNEY, WILLIAM G. Mor'r. 

